Bloomingdale's new b-tags block used dress returns

Tired of customers returning used clothing, Bloomingdale's has begun attaching chunky, 3-inch black plastic tags to dresses costing more than $150 and leaving them on after their sale.

The special "b-tags," as they are called, are attached to visible places like the front bottom hemline to make them difficult to hide when the item is worn. Once the black plastic tag is removed, the garment cannot be returned.

Bloomingdale's is using the tags to help crack down on a practice so common it has its own name: wardrobing. That's when someone purchases a clothing item, wears it out once or twice—like to a party—and then returns it to the store.

Adam Jeffery | CNBC

Bloomingdales introduce B-Tags to crack down on returned clothing after being worn.

"What people don't realize is that it's an illegal process, and it's also known as return fraud," said retail analyst Hitha Prabhakar.

About 65 percent of retailers said shoppers returned used clothing last year, according to a November survey conducted by the National Retail Federation. The group estimates the practice cost the industry $8.8 billion last year.

Analysts say the tactic may be seen as a risky gamble that could scare customers away to competitors, like Nordstrom, which has no plans to implement a similar system.

"These b-tags are in place to reinforce the fact that Bloomingdale's will be unable to accept a return of merchandise that has been damaged, worn, washed, used and/or altered," the retailer said in a statement.

"I probably wouldn't want to get an outfit from a store (if) someone had already worn it," said one shopper outside Bloomingdale's flagship store in New York City.

"A lot of people wear it to a party once and then return it, which isn't fair to the next person at all," another shopper told TODAY.